The present disclosure relates to a shut-off valve apparatus and particularly to a shut-off valve apparatus having a pneumatic actuator that moves a valve between an opened and a closed position. More particularly, the present disclosure relates to a shut-off valve apparatus having a pneumatic exhaust controller that operates to control the movement of pressurized air into and out of the pneumatic actuator.
Shut-off valves that open and close to control material flow in a conduit or piping system are known. The opening and closing of some known shut-off valves are controlled by pneumatic or electrical signals. Some conventional shut-off valves, such as those included in piping systems though which combustible fuel is delivered, are configured to close very rapidly. Rapid closing in such valves is desirable, for example, when an alarm condition is present or if electrical or pneumatic inputs to the valve are severed or otherwise lost.
According to the present disclosure, a shut-off valve apparatus has a valve body and a valve member coupled to the valve body. The valve member is movable between a first position blocking material flow through the valve body and a second position permitting material flow through the valve body. A pneumatic actuator receives pressurized air to move the valve member from the first position to the second position. A pneumatic exhaust controller controls the flow of pressurized air into and out of the pneumatic actuator.
In illustrative embodiments, the pneumatic exhaust controller comprises a manifold having a first portal coupled to a source of pressurized air, a second portal, and an exhaust portal. The pneumatic exhaust controller has regulator means coupled to the manifold for closing the exhaust portal in response to pressurized air from the air source being communicated to the regulator means through the first portal and for passing pressurized air from the pressurized air source to the second portal when pressurized air from the source is communicated to the regulator means through the first portal.
Also in the illustrative embodiments, an electrical actuator, such as a solenoid valve, is coupled to the manifold and is operable to block and unblock pneumatic communication between the first portal and both the second portal and the exhaust portal. In one of the illustrative embodiments, a check valve is coupled to the manifold and the regulator means comprises a diaphragm and a guide coupled to the diaphragm. In this embodiment, the manifold has a guide-receiving passage that receives a portion of the guide. As the regulator means moves relative to the manifold block, the guide maintains proper alignment of the diaphragm relative to the manifold.
Additional features will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments exemplifying the best mode of carrying out the pneumatic exhaust controller as presently perceived.